- Email: [email protected]
OR 46 Comparison of varying the depth of heat application on the adaptability of gutta-percha during warm vertical compaction
Vol. 25, No. 4, April 1 9 9 9
:OR
Influence of root canal sealers on inflammatory reactions in cell cultures. B. Willershausen *l, B. Brise/Yo Marroqu/n I, D. SchOfer2 and W. Mann'-
~Department of Operative Dentistry, 2Department of Otorhinolaryngology, Johannes Gutenberg University, Mainz, Germany The biological effect and possible arouse of inflammatory reactions of root canal sealers on surrounding tissues are rather relevant for the outcome of a root canal treatment. The aim of this study was to measure the influence of various root canal sealers and gutta-percha points on cell growth and production of inflarrmlatory markers in vitro by means of cell cultures. Gingival fibroblasts between the 3th to 7th passage were cultured with different root canal sealers (AH Plus, Ketac Endo, Endion), a retrograde sealer (Super EBA) and calcium hydroxide based (as matrix) gutta-percha points. Wells with only fibroblasts served as negative controls. Sealapex and regular gutta-percha points were used as positive controls. 12 wells (3x l0 ~cells/well; 0.12 mg protein/ml) were covered and incubated with each sealer with a mean weight of 2.5 mg (_+0.1 rag). Cell growth (protein mg/ml, cell number and vital staining) was determined after a period of 6 days of incubation. The inflammatory influence of the sealers was determined through the release of prostaglandin E2 (PGE2, clone E2R 1) with fibroblasts ( 15.000 cells/ well) which were incubated during 30 nfin. In addition the fibroblasts cultures were stimulated with arachidonic acid (105 M). The results were statistically analysed with the Kruskal-Wallis test (p=0.00 t ). The cell growth results showed si~o'nificantdifferences between the tested materials and the positive and negative controls (vital staining, cell number). The release of lipid mediators as a sign of inflammation in comparison to the negative controls showed significant differences to most materials with exception of Sealapex and regnlar gutta-percha. This study provides information on possible inflammatory effects of root canal filling materials. These results could prove useful when selecting root canal sealers with a lower irritation potential. OnO=R] ZZA
N o c i e e p t o r morphology in inflamed dental pulps.
G.R. Holland*, S.M. AI-Hadlaq, M, VN. Narhi*, P Landry
U. Michigan and #U. Turku, Finland The role of C fibers in the response to tissue injury is complex. There may be one group of fibers that respond primarily to the threat of injury and a second that respond only when injury actually occurs. Some or all C fibers appear to sprout in or around injury sites and, somewhat perversely, contribute to the inflammation that they detect by releasing peptides. We hypothesize that different components of the inflammatory process may be related to different components of the neural response. Under general anesthesia acid etched cavities were prepared in the teeth of adult dogs. Human caries was placed on the cavity floor and the cavity filled with composite resin. After 7 days the dental pulp beneath the cavities was examined using immunohistochemical techniques, morphometry & densitometry followed by the determination of correlation coefficients. The incidence of panaxonal marker Protein Gene Product 9.5 staining nerves cotxelates with the polymorphonuclear leukocyte (PMN) population (r=0.78) & the intensity of staining for Heat Shock Protein 70 (HSP 70) (r=0.73) but not with Interleukin I (ILl) staining (r=0.17). The incidence of Calcitonin Gene Related Peptide staining is only weakly correlated with either ILl (r=0.57) or the presence of PMNs (r=0.26) but more substantially with HSP 70 (r=0.69). Neural sprouting and the extent of neuropeptide accumulation may be related to different elements of the injury response. Supported by the AAE Foundation.
Journal of Endodontics 4, 293
O~tl
In-vitro efficacy of microscope and dye on identifying root canals in root end resection. S.F. Yang*, J.R. Hsu, S.F. Pai, C.L. Tsai
Veterans General Hospital-Taipei, National YangM i n g University, Taiwan Identifying the root canal and isthmus is important for the success of surgical endodontic procedures. This study evaluated the efficacy of the surgical operating microscope and methylene blue dye in identifying the canal and isthmus during root end resection. Root end resection was performed on mesiobuccal root of thirty human maxillary first molars at 1/3 and 1/2 levels. Color slides of resected root with and without methylene blue dye were made at 1:1,7.5X and 25X using a stereomicroscope. All slides were blindly evaluated by two independent endodontic residents for the number of root canals and presence of isthmus. The gold standard of number of root canal and presence of isthmus was determined by an experienced endodontist. The accuracy of two viewers in determining the number of root canals and the presence of an isthmus was evaluated with microscope magnification but no dye, with dye but no microscopic magnification, and under microscopic magnification with dye. Logistic regression was used for statistical analysis. The results indicated that using the microscope without dye increased the reading accuracy of the isthmus for one viewer. Using dye without the microscope increased the reading accuracy of the number of canals for another viewer. Using tile microscope with dye produced a statistically significant (p<0.05) increased reading accuracy (about 20%) of the number of canals for both viewers and presence of isthmus for one viewer.
O~ I Comparison of varying the depth of heat application on the adaptability of gutta-percha during warm vertical compaction. R.S. Smith*, R.N. Weller, R.J. Loushine, W.F Kimbrough T h e Medical College of Georgia, Augusta, G A The three-dimensional obturation of the complex root canal system is imperative after cleansing and shaping to achieve a predictable outcome. The purpose of this study was to compare the adaptability of gutta-percha while varying the depth of heat application to obturate a standard root canal. A split-tooth model was constructed using a human maxillary central incisor. The root canal was cleaned and shaped using a step-back preparation to a size #60 Flex-O-File at the working length (WL). Five shallow depressions were artificially produced on the root canal wall. Twenty obturations were performed for each technique (Obtura II, lateral condensation, warm vertical compaction with heat applications at 3 ram, 4 ram, 5 ram, and 7 mm from the WL). After each obturation, the model was separated and the mesial and distal sides of each obturation were examined and videotaped at x32 magnification. The quality of the obturation was evaluated based on the replication to the WL, replication of the artificial depressions, surface adaptation, and homogenicity of the gutta-percha. ANOVA and the Student-Newman-Keuls tests indicated that all the techniques were significantly different fiom each other (p<0.05) except for the Obtura II group and the warm vertical compaction with the heat application to 3 mm from the WL (p>0.05). The obturations were ranked with the Obtura II injectable technique best followed by the warm vertical compaction with heat application at 3 ram, 4 ram, 5 ram, and 7 mm and finally the lateral condensation technique.
:OR
Influence of root canal sealers on inflammatory reactions in cell cultures. B. Willershausen *l, B. Brise/Yo Marroqu/n I, D. SchOfer2 and W. Mann'-
~Department of Operative Dentistry, 2Department of Otorhinolaryngology, Johannes Gutenberg University, Mainz, Germany The biological effect and possible arouse of inflammatory reactions of root canal sealers on surrounding tissues are rather relevant for the outcome of a root canal treatment. The aim of this study was to measure the influence of various root canal sealers and gutta-percha points on cell growth and production of inflarrmlatory markers in vitro by means of cell cultures. Gingival fibroblasts between the 3th to 7th passage were cultured with different root canal sealers (AH Plus, Ketac Endo, Endion), a retrograde sealer (Super EBA) and calcium hydroxide based (as matrix) gutta-percha points. Wells with only fibroblasts served as negative controls. Sealapex and regular gutta-percha points were used as positive controls. 12 wells (3x l0 ~cells/well; 0.12 mg protein/ml) were covered and incubated with each sealer with a mean weight of 2.5 mg (_+0.1 rag). Cell growth (protein mg/ml, cell number and vital staining) was determined after a period of 6 days of incubation. The inflammatory influence of the sealers was determined through the release of prostaglandin E2 (PGE2, clone E2R 1) with fibroblasts ( 15.000 cells/ well) which were incubated during 30 nfin. In addition the fibroblasts cultures were stimulated with arachidonic acid (105 M). The results were statistically analysed with the Kruskal-Wallis test (p=0.00 t ). The cell growth results showed si~o'nificantdifferences between the tested materials and the positive and negative controls (vital staining, cell number). The release of lipid mediators as a sign of inflammation in comparison to the negative controls showed significant differences to most materials with exception of Sealapex and regnlar gutta-percha. This study provides information on possible inflammatory effects of root canal filling materials. These results could prove useful when selecting root canal sealers with a lower irritation potential. OnO=R] ZZA
N o c i e e p t o r morphology in inflamed dental pulps.
G.R. Holland*, S.M. AI-Hadlaq, M, VN. Narhi*, P Landry
U. Michigan and #U. Turku, Finland The role of C fibers in the response to tissue injury is complex. There may be one group of fibers that respond primarily to the threat of injury and a second that respond only when injury actually occurs. Some or all C fibers appear to sprout in or around injury sites and, somewhat perversely, contribute to the inflammation that they detect by releasing peptides. We hypothesize that different components of the inflammatory process may be related to different components of the neural response. Under general anesthesia acid etched cavities were prepared in the teeth of adult dogs. Human caries was placed on the cavity floor and the cavity filled with composite resin. After 7 days the dental pulp beneath the cavities was examined using immunohistochemical techniques, morphometry & densitometry followed by the determination of correlation coefficients. The incidence of panaxonal marker Protein Gene Product 9.5 staining nerves cotxelates with the polymorphonuclear leukocyte (PMN) population (r=0.78) & the intensity of staining for Heat Shock Protein 70 (HSP 70) (r=0.73) but not with Interleukin I (ILl) staining (r=0.17). The incidence of Calcitonin Gene Related Peptide staining is only weakly correlated with either ILl (r=0.57) or the presence of PMNs (r=0.26) but more substantially with HSP 70 (r=0.69). Neural sprouting and the extent of neuropeptide accumulation may be related to different elements of the injury response. Supported by the AAE Foundation.
Journal of Endodontics 4, 293
O~tl
In-vitro efficacy of microscope and dye on identifying root canals in root end resection. S.F. Yang*, J.R. Hsu, S.F. Pai, C.L. Tsai
Veterans General Hospital-Taipei, National YangM i n g University, Taiwan Identifying the root canal and isthmus is important for the success of surgical endodontic procedures. This study evaluated the efficacy of the surgical operating microscope and methylene blue dye in identifying the canal and isthmus during root end resection. Root end resection was performed on mesiobuccal root of thirty human maxillary first molars at 1/3 and 1/2 levels. Color slides of resected root with and without methylene blue dye were made at 1:1,7.5X and 25X using a stereomicroscope. All slides were blindly evaluated by two independent endodontic residents for the number of root canals and presence of isthmus. The gold standard of number of root canal and presence of isthmus was determined by an experienced endodontist. The accuracy of two viewers in determining the number of root canals and the presence of an isthmus was evaluated with microscope magnification but no dye, with dye but no microscopic magnification, and under microscopic magnification with dye. Logistic regression was used for statistical analysis. The results indicated that using the microscope without dye increased the reading accuracy of the isthmus for one viewer. Using dye without the microscope increased the reading accuracy of the number of canals for another viewer. Using tile microscope with dye produced a statistically significant (p<0.05) increased reading accuracy (about 20%) of the number of canals for both viewers and presence of isthmus for one viewer.
O~ I Comparison of varying the depth of heat application on the adaptability of gutta-percha during warm vertical compaction. R.S. Smith*, R.N. Weller, R.J. Loushine, W.F Kimbrough T h e Medical College of Georgia, Augusta, G A The three-dimensional obturation of the complex root canal system is imperative after cleansing and shaping to achieve a predictable outcome. The purpose of this study was to compare the adaptability of gutta-percha while varying the depth of heat application to obturate a standard root canal. A split-tooth model was constructed using a human maxillary central incisor. The root canal was cleaned and shaped using a step-back preparation to a size #60 Flex-O-File at the working length (WL). Five shallow depressions were artificially produced on the root canal wall. Twenty obturations were performed for each technique (Obtura II, lateral condensation, warm vertical compaction with heat applications at 3 ram, 4 ram, 5 ram, and 7 mm from the WL). After each obturation, the model was separated and the mesial and distal sides of each obturation were examined and videotaped at x32 magnification. The quality of the obturation was evaluated based on the replication to the WL, replication of the artificial depressions, surface adaptation, and homogenicity of the gutta-percha. ANOVA and the Student-Newman-Keuls tests indicated that all the techniques were significantly different fiom each other (p<0.05) except for the Obtura II group and the warm vertical compaction with the heat application to 3 mm from the WL (p>0.05). The obturations were ranked with the Obtura II injectable technique best followed by the warm vertical compaction with heat application at 3 ram, 4 ram, 5 ram, and 7 mm and finally the lateral condensation technique.